Bump antlr4.version from 4.5.1 to 4.9.2

Bumps `antlr4.version` from 4.5.1 to 4.9.2.

Updates `antlr4-runtime` from 4.5.1 to 4.9.2
- [Release notes](https://github.com/antlr/antlr4/releases)
- [Changelog](https://github.com/antlr/antlr4/blob/master/CHANGES.txt)
- [Commits](https://github.com/antlr/antlr4/compare/4.5.1...4.9.2)

Updates `antlr4-maven-plugin` from 4.5.1 to 4.9.2
- [Release notes](https://github.com/antlr/antlr4/releases)
- [Changelog](https://github.com/antlr/antlr4/blob/master/CHANGES.txt)
- [Commits](https://github.com/antlr/antlr4/compare/4.5.1...4.9.2)

Signed-off-by: dependabot[bot] <support@github.com>

Closes #88

Change-Id: I1db4b02cca0396a0126aa6d1380d9c76c5900de6
diff --git a/pom.xml b/pom.xml
index cf0df67..a8e7d9c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -37,7 +37,7 @@
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>		
 		<jackson.version>[2.9.5,)</jackson.version>
-		<antlr4.version>4.5.1</antlr4.version>
+		<antlr4.version>4.9.2</antlr4.version>
 		<antlr3.version>3.5.2</antlr3.version>
 		<java.version>1.8</java.version>
 		<log4j.version>2.14.1</log4j.version>